BySteve Gorman and R.T. Watson, ReutersFebruary 13, 2012

Flowers were placed on a Grammy sidewalk plaque honoring Whitney Houston's wins for Record of the Year and Album of the Year in 1994 outside the Grammy Museum in Los Angeles, Feb. 12, 2012. Houston died Saturday, Feb. 11, on the eve of the 54th Grammys.

Los Angeles — Coroners on Sunday completed their autopsy on the body of singer Whitney Houston and confirmed that she was found in the bathtub of her Beverly Hills hotel room, but said the cause of death would not be determined until more lab tests were completed.

Ed Winter, assistant chief coroner for Los Angeles County, revealed little about the autopsy at a news conference Sunday, but said medical examiners found no visible signs of trauma or foul play.

He declined to comment on various media reports that Houston, 48, had drowned in her hotel bathtub, possibly after succumbing to drugs or alcohol. He added, "I'm not going to comment on any of the meds or prescriptions that were obtained."

"I'd just comment that she was found in the bathtub. ... I believe somebody removed her from the bathtub and the paramedics did CPR (cardiopulmonary resuscitation) on her."

He said toxicology tests, which would take six to eight weeks to conduct, would be necessary to determine what factor, if any, drugs or alcohol might have played in Houston's death.

On Monday, the Beverly Hills police also worked to keep a lid on growing media speculation about Houston's death.

"As can be expected in a high profile incident such as this there have been many rumors circulating and much speculation by the media and the public," Beverly Hills Police said in the statement. "In order to minimize such speculation, the Beverly Hills Police Department has asked the Coroner's office to place a security hold on their findings until they have a complete and final report prepared."

'Detectives are still probing the death and will release few details until they have completed their inquiry, Beverly Hills Police spokesman Lieutenant Mark Rosen said at a news conference on Monday. "We are not conducting a homicide investigation at this time. We do not know the cause of death, we do not know the circumstances leading up to her death," Rosen said.

"We've had a death in our family and so at least for me ... the only thing that feels right is to begin with a prayer for a woman we loved, for our fallen sister, Whitney Houston," he said.

His brief prayer was followed by a clip of Houston singing her hit, "I Will Always Love You," as the crowd responded with a standing ovation.

Houston, who enjoyed tremendous professional success but struggled with drug abuse for years, died on Saturday afternoon in a fourth-floor room at the Beverly Hilton Hotel. She was at the hotel to attend an annual pre-Grammy gala held that evening by her mentor, record mogul Clive Davis.

The Grammy salute Sunday capped an emotional day for those closest to the pop diva and those who admired her as an entertainer. From the New Jersey church where Houston's singing career first took flight to the hotel where her life abruptly ended, family and fans expressed their grief on Sunday with prayer, tears and raw anguish.

A fire department spokeswoman declined to disclose any information about the daughter's medical condition but said she was "awake and talking" at the time she was transported.

Brown, who was reported by celebrity news website TMZ.com as being enraged at authorities for not being allowed into the hotel room where her mother's body was found, was treated at the hospital for stress and released, a source close to the family told Reuters. A hospital spokeswoman declined comment.

At the New Hope Baptist Church in Newark, New Jersey, Houston's hometown, fans and admirers gathered to celebrate her life during three Sunday services, portions of which were devoted to the singer and her family.

Cards and flowers were tied to the railings of the church, where congregants hugged and cried at the entrance. Among those paying their respects was the Reverend Jesse Jackson, the civil rights activist.

"The suddenness of it all leaves us traumatized," said Jackson, who watched Houston grow up and sing at New Hope. It was in that red brick church on a quiet backstreet near downtown Newark where Houston's career began as a soloist in a gospel choir in the 1970s.

While the cause of Houston's death remained undetermined, media reports on Sunday focused on her public behavior in the hours before her death.

The Los Angeles Times said Houston, disheveled, sweaty and smelling of alcohol, was behaving erratically when she stopped by the Hilton two days earlier, accompanied by her daughter, for rehearsals. She was seen flailing her hands frenetically, skipping around the ballroom and wandering aimlessless through the lobby, the newspaper said.

Members of Houston's family expressed their grief in a brief statement saying they were "devastated" by her loss.

"This is an unimaginable tragedy and we will miss her terribly," it said. "We appreciate the outpouring of love and support from her fans and friends."

In a separate statement issued through People magazine, former husband Bobby Brown, with whom she had shared a long struggle with substance abuse, said, "I am deeply saddened at the passing of my ex-wife, Whitney Houston."

Brown was described by an unnamed relative as "beside himself" with grief, according to the magazine.

On the West Coast, the First AME Church of Los Angeles, the city's oldest African-American congregation, held a special moment of silence in Houston's memory.

"Many of us were rooting and pulling for her because she has been a blessing to this generation with talent, with a special anointed voice," Pastor John Hunter told parishioners. "We will miss her. This world will miss her."

Houston's songs were already dominating Internet music sales early on Sunday. Her album "Whitney Houston - The Greatest Hits" was the top seller in the music category on Amazon.com, and her signature hit, "I Will Always Love You," was the No. 1 download at iTunes.

Over the course of a 30-year career in which she established herself as one of the most-admired and influential singers of her time, Houston won six Grammys, 30 Billboard awards and 22 American Music Awards.

The soundtrack for the hit movie in which she starred, "The Bodyguard," was among the best-selling film soundtracks ever.

By the early 1990s, Houston's success on stage was accompanied by an increasingly troubled personal life. In 1992 she married singer Bobby Brown and their tumultuous 14 years together were marred by drug abuse and domestic violence.

The last 10 years of Houston's life were dominated by drug use, rumors of relapses and trips to rehab. (Additional reporting by R.T. Watson, Mary Slosson, Jill Serjeant, Dan Whitcomb and Piya Sinha-Roy.; Editing by Steve Gorman, Dan Burns and Stacey Joyce)